Coupling device for detachably securing sunshades, filter holders, and like accessories to the lens barrels of cameras



June 7, 1949. NAGEL 2,472,307

COUPLING DEVICE FOR DETAGHABLY SECURING SUNSHADES, FILTER HOLDERS, AND LIKE ACCESSORIES TO THE LENS BARRELS OF CAMERAS Filed Jan. 25, 1946 Patented June 7, 1949 UNITED STATES ATENT OFFICE COUPLING DEVICE FOR DETACHABLY SE- CURING SUNSHADES, FILTER HOLDERS, AND LIKE ACCESSORIES TO THE LENS BARRELS OF CAMERAS 4 Claims.

This invention relates generally to coupling devices employed for removably securing such accessory parts as lens shades, light filter mounts, and like light regulating implements to photographic cameras.

It is an object of the present invention to provide means simple in construction and manipulation for readily and securely attaching light regulating implements to a carrier, such as the lens barrel of a camera, and for removal therefrom; said means tending to constrict certain portions of the coupling device around the lens barrel over which it is fitted, whereby it will firmly frictionally grip the barrel and hold its position thereon.

Another object of the invention is to provide means affording the frictional securement of a split coupling ring around a lens barrel without requiring relative rotary movement of the interengaging parts of the device so that the location and securement of the device upon the lens barrel and its ready removal therefrom, when desired, will be materially simplified.

Still another object of the invention is to provide means readily accessible for effecting a coupling action of a split ring around the lens barrel for securing the device in place thereon, such means including a radially-extending pressure element, such as a set screw, that is manually operative to effect a constricting action of the ring with respect to the lens barrel.

A still further object of this invention is the provision of means ensuring a lever-like actuation of the coupling ring device with respect to the carrier or lens barrel to which it is to be attached in frictional and clamping relation.

These and other objects of the invention are obtained, a more particular description of which appearing hereinafter and being set forth in the claims appended hereto.

In the accompanying drawing:

Fig. 1 is a side elevation of the coupling device made in accordance with this invention, shown partly in section, and applied to a lens barrel of a camera and carrying a lens shade.

Fig. 2 is a sectional view of parts of the device, shown in a modified construction.

Fig. 3 is a sectional view of parts of the device in a further modified form.

With reference to the structure shown in Fig. 1 of the drawing, numeral 10 indicates the forward portion of a photographic camera terminating into a lens carrier barrel ll of the conventional character to which a lens shade l2 or other light regulating implement is adapted to be removably attached, as will be hereinafter described.

For the attachment of the lens shade I2, a

coupling device I3 is provided which is adapted to engage the shade 12 or any other preferably tubular member and secure the same to the lens barrel. The coupling device includes a holding member l4 and a sleeve member I5. Holding member [4 is tubular in cross section and is rovided with an inner annular rim l6, dividing said member l4 into a forward portion l1 and a rearward portion [8. Forward portion I! is internally threaded to accommodate the threads 20 provided at the end portion of the lens shade. The rearward portion I8 of holding member I4 is provided with an annular groove 2| for the reception of a flange or projecting portion 22 provided at one end of the sleeve or split ring l5, this interengagement of the flange 22 with the groove 2| of the member I4 serving to prevent separation of the sleeve l5 from the member l4 in an axial direction of the device.

The sleeve or split ring I5 is also formed with an inwardly extending annular flange 23 which forms an abutment against the forward end of the lens barrel, as shown in Fig. 1, when the coupling device is fitted in position thereon, th.ereby properlv locating it with respect to the barrel.

The sleeve member or split ring I5 is provided with an inverted V-shaped slot 29 extending transversely across the sleeve. It will be understood that this slot may be straight or may be differently shaped, but it is preferred to employ the inverted V-shape for the purpose of positively guiding the spaced apart slit ends together when the sleeve or ring is constricted in a manner to be described.

For the purpose of causing the sleeve or split ring to exert clamping pressure about the lens barrel to thereby firmly grip the barrel and hold the coupling device in position thereon, or in other words, to be constricted around the barrel, a pressure exerting element, such as a set screw 30, which is threaded through the holding member 14, is urged into a recess 3| provided in the sleeve or split ring 15 for its accommodation. Set screw 36 is provided with a knurled head 32 by means of which it may be turned, when it is desired either to secure the coupling device in position on or to remove it from the lens barrel.

It will be noted that when the device is sepa-' rated from the camera, and the set screw 30 is thus loosened for that purpose, the slot 29 will be opened to its maximum position, as indicated by the dotted line 34. When the device is fitted in position on the lens barrel, as indicated in Fig. l and the set screw is manually turned inwardly,

the opposite side of the slot 29 from moving or' sliding away from the portion of the sleeve that is sprung towards it by pressure of the set screw 30. For this purpose, it might beconsidered'useful to maintain that portion in position by any suitable fixing means, such as projection and notch engagement, although this will possibly-"be" necessary in cases of lense barrels having relatively large diameter. From the arrangement described, it will be clear that the device can be fitted in place and securely clamped about the lens barrel by tig'hteningmr'pre'ssure exertion by'means of the set screw '30.

In'Fig. 2 is shown 'a'modified construction of the coupling device wherein the sleeve I3 is provided with'intrengaging formations, namely, external1y-"located'screw threads 40 which loosely engage screw threads 4| provided on the'interior of .thejinherpcrtion" ll! of the holding member I4. The setsc'i'ew 3!],inthis embodiment, unctions'asjdescribedwith respect to the embodimerit of "Fig; 1"a'n'd "serves also to hold'the mem-' In the several embodiments ofthe invention shown and described, it will be clear that the placement of the device in position upon a lens barrel'is" considerably simplified and efiective.

Sleeveor'split ring I5 is merely slipped in position' about the'lens'barrel and the set screw 30' operated to the extent required to constrict the ringl51tightly about the lens barrel so as to cause it, to'fric tio'nally grip the same and hold its position thereon. When the set .screw is loosened, the springiness of the ring l5 causes it to; spread or open to the extent required to enable it to'be'slipped from the barrel. The position of the set screw 30,'extending radially from'the device and exposed for easy manipulation enablesthe .deviceto be easily and conveniently fitted in place or removed, and the removal of the Iensshade o r filters interposed between thesame and the forward part of theholding member M can be done at, any time without requiring removal of the holding member l4. These and other advantages will be readily apparent to s -.s si 'l d n 1 1 5 a v,

It is well understood that the split ring I 5 may be made fromany suitable springy material or may be made fr om,a'p lastic composition, such as knownjin'thetrade under the name of Bakelite, and that aplurality or set of such interchangeable split ri ngs rnay be employed in connection withtheholdingmember 7 l4, it being understood that the inner diameter of the split ring [5 may vary in accordance with the dimensions and make of the lens barrel.

While several embodiments of the invention are hereinabove described, it will be apparent that the same is not to be restricted thereto, but is broad enough to cover other structures coming the scope of the'annexed claims.

Having thus "described theinvention, what is claimed as new and desired to be secured by Letters Patent, is:

1. In a device of the character described, a tubular'hdldifig niemjber having an inrier surface,

I for" detachably fixin a camera lens attalcliment to said holding member, said holding nifiiber having'an'iri'clined portion on said inner surfacewa split ring having an outer inclined peripheral surface complementary to and coacting" vv'ith' sai d"inclind portion of said tubular holding member, a shoulder extending from said inner surface of said tubular holding member against whichsaid-split ring laterally abuts, and

an: em ritithieadd throughsaid'tubul'a'r holding-'niemberand' engageable'with" said split ring to'ibearagainst and contract the latter 'about'a lens barrel. v v

2, In a device of the character described, a tubularjholdiiig'mmber having ap'o'rtion adapted to ,dtachably,rcivfalens attachment, said tubular" member having a rearward part pro vided' with'adinher surface havingthreads, a splitringhavin'glitsoutrl face" threaded for re cepnoa 'byl the'thread's or 'said' tubular member, and aset screw threadedthrou'glfthe tubular member engageable' against the threaded outer mes 'ofsai'd' split ri'ng to cause contraction oflsalidring aroundalensbarrel over which'said split ring'is laced.

device 'o'fthe character described, an outef'tubiilfarfni niberforc'arryin'g a light regulat ng attachment, a split'ring'placed for position in said tubular member "and terminating in a'V-s'hapedslot," intereng'a'ging formations, respectively, arranged on'th outer surfa'ceof'said spli't'ringfand' on"th'e' innersurface of said tubular"meinber"ior holdingsaid'split ring in posimadamtojmpedesepa auoa from; each other in axial direction, an annular rim' within said tubula'r ifiei'nb'er against which said split ring laterally abuts; a'i rfa set screw threade'dly extending through saidputer tubular' member and operativ ely engageabl'e with" a araqn; of said split ringjyvhei'ebyjsaid screw 'is enabled to narrow the v-shap'dslot'of said ringwhen said set screw is tilieaaeaagamst said rin'g'and to constrict said ring about a le n'sbarr'el'to which said ring may be pplied? I p 4;. al device of the character" described; a holding aterar carrying a lens attachment, meansfor' coupling sa'id holding member to a lens barrel of a camera, sa'id'm'eans including a ringsplit across its periphery so as to p'r'ovide ends, a projecting portion provided paths outer surface of said split ring, a recessprovided in thefinnersurface of said holding memberand'conformed'to the shape of and meeting with'said'prdjecting portion, said holding member beirig'prbvi ded with an inner annular 'ri'n i' adapted for" lateral abutment of said projecting portion against said'rim, wherebysaid split; ring' may 1313' Held in position Within said hdl diri gfniember tb'prvem' separation from each othe' direction; and adjusting means cared by and passing through said holding memberiand opera le agaiiis'tsaid split ring to' contract tli eiid's" thereof, to therebybringabout tight frictional surface engagement of said split ring with said lens barrel to which said holding UNITED STATES PATENTS Name Date Barnes June 5, 1917 Glenn Dec. 3, 1918 Green Nov. 4, 1930 Guhl May 13, 1941 FOREIGN PATENTS Country Date Germany Dec. 12, 1923 Great Britain Apr. 18, 1929 

